Answer:
A) 68.33%
B) (234, 298)
Step-by-step explanation:
We have that the mean is 266 days (m) and the standard deviation is 16 days (sd), so we are asked:
A. P (250 x < 282)
P ((x1 - m) / sd < x < (x2 - m) / sd)
P ((250 - 266) / 16 < x < (282 - 266) / 16)
P (- 1 < z < 1)
P (z < 1) - P (-1 < z)
If we look in the normal distribution table we have to:
P (-1 < z) = 0.1587
P (z < 1) = 0.8413
replacing
0.8413 - 0.1587 = 0.6833
The percentage of pregnancies last between 250 and 282 days is 68.33%
B. We apply the experimental formula of 68-95-99.7
For middle 95% it is:
(m - 2 * sd, m + 2 * sd)
Thus,
m - 2 * sd <x <m + 2 * sd
we replace
266 - 2 * 16 <x <266 + 2 * 16
234 <x <298
That is, the interval would be (234, 298)
Answer:
1.155
Step-by-step explanation:
Answer:
They're both acute
Step-by-step explanation:
They both meausre less than 90°
A right angle would look like an L (it could be a flip L as well)
And an obtuse angle is anything bigger than a right angle
33-4(3)
33-12
21
The answer is 21
Answer:
x = 7000
y = 5600
(7000, 5600)
Step-by-step explanation:
To solve the system of equations means to find the point of intersection (graphically). You are finding what value of 'x' and what value of 'y' fits both equations.
x = y + 1400
0.08x + 0.05y = 840
We can solve using the method <u>substitution</u>, where you replace a variable in one equation with an equivalent expression.
<u>Since "x" is y + 1400, we can replace "x" in the second equation.</u>
0.08x + 0.05y = 840
0.08(y + 1400) + 0.05y = 840
Distribute over brackets by multiplying 0.08 with y, then 0.08 with 1400.
0.08y + 112 + 0.05y = 840 Collect like terms (with "y" variable)
112 + 0.13y = 840
Now isolate "y" in the simplified equation.
112 - 112 + 0.13y = 840 - 112 Subtract 112 from both sides
0.13y = 728
0.13y/0.13 = 728/0.13 Divide both sides by 0.13
y = 5600 Solved for y
We can substitute "y" with 5600 in any other equation that has "x".
x = y + 1400
x = 5600 + 1400 Add
x = 7000 Solved for x
You may express the answer as a coordinate, or an ordered pair (x, y).
The solution is (7000, 5600).
